Firstly, the rarity of these cards is a significant factor
As an Orzhov commander, a Selenia player has access to the numerous black tutors, making this strategy more consistent than it may be otherwise
Ruby, Daring Tracker is an excellent signpost for this archetype : Not only does she produce mana of both colors, allowing you to get your bigger threats sooner, but she also gets stronger whenever she attacks while you control a creature with at least four power
Additionally, whenever Svyelun attacks, you can draw a card
A quick glance at its price history showed me that this piece of shiny cardboard that my girlfriend had ferried around from crappy apartment to crappy apartment was not only pricey but, thanks to a global pandemic that had renewed interest in collectible cards, more valuable than ever